A mortality analysis of septic shock, vasoplegic shock and cryptic shock classified by the third international consensus definitions (Sepsis-3)

Introduction: This study aimed to compare the 28-day mortality of patients with septic shock, defined by Sepsis-3 criteria and patients with vasoplegic or cryptic shock who are excluded from this new definition.

Objectives: This retrospective observational study was performed using a tertiary emergency department's septic shock registry and investigated the records of patients managed between January 2010 and December 2015. In 2,138 total patients, 1004 (47.0%) had septic shock, 476 (22.2%) had vasoplegic shock and 655 (30.6%) had cryptic shock.

Results: There was significant variation in 28-day mortality among the three groups: 23.4% for septic shock, 8.8% for vasoplegic shock and 12.2% for cryptic shock (P < .001). In subgroup analysis of cryptic shock or septic shock according to lactate levels (2-3, 3-4 and >4 mmol/L), the mortality rate increased as lactate increased (cryptic shock: 9.5%, 14.8% and 18.0%; septic shock: 18.6%, 22.6% and 27.0%, respectively; P < .001). Multivariable analysis revealed odds ratios for mortality of 0.31 (95% CI 0.22-0.44; P < .001) for vasoplegic shock and 0.46 (95% CI 0.35-0.61; P < .001) for cryptic shock relative to septic shock. Survival curve analysis showed significant differences among patients with septic shock, vasoplegic shock and cryptic shock (Log rank test: P < .0001).

Conclusion: The new septic shock definition may be useful for identifying high-risk patients requiring intensive care. However, cryptic shock-associated mortality increased to 18.0% as serum lactate increased, which suggests that some cryptic shock patients may also require intensive management.